Modeling and Experiments of In-Tube Condensation Heat Transfer for R22 and Its Alternative Refrigerant

In-tube condensation heat transfer has been investigated experimentally and theoretically. To study the condensation heat transfer characteristics of R22 and its alternative refrigerant R410A, a series of experiments were performed, and the experimental results are presented and compared with previous works. Also, a condensation heat transfer modeling is presented for two-phase turbulent annular flow inside smooth tubes. This model can account for the effects of interfacial shear stress and liquid entraimment as well as the turbulent eddy viscosity on the condensation heat transfer. Using this calculation model, local condensation heat transfer coefficients for annular flow inside horizontal smooth tubes were obtained, and the calculated values were compared with present experimental results of condensation heat transfer for R410A together with the existing correlations.